package Network.homework;

import Network.UdpDirecService;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;

public class UdpEchoServer {
    private DatagramSocket socket=null;
    public UdpEchoServer(int port) throws SocketException {
        socket=new DatagramSocket(port);
    }
    public void start() throws IOException {
        System.out.println("服务端启动");
        while(true){
            //1.接收客户端请求
            DatagramPacket requestPacket=new DatagramPacket(new byte[4096],4096);
            socket.receive(requestPacket);
            //2.根据请求,解析响应
            String request=new String(requestPacket.getData(),0,requestPacket.getLength());
            String response=process(request);
            //3.返回响应
            DatagramPacket responsePacket=new DatagramPacket(response.getBytes(),response.getBytes().length,
                                                        requestPacket.getSocketAddress());
            socket.send(responsePacket);
            System.out.printf("[%s,%d],req:%s, resp:%s\n",requestPacket.getAddress(),requestPacket.getPort(),
                                                            request,response);
        }
    }

    public String process(String request) {
        return request;
    }

    public static void main(String[] args) throws IOException {
        UdpEchoServer udpEchoServer = new UdpEchoServer(9090);
        udpEchoServer.start();
    }
}
